1. Field of the Invention
The present invention relates to an engine starting system and method. More particularly, the present invention relates to an engine starting system and method for starting a 4-stroke engine using a recoil starter.
2. Description of the Background Art
It is known that some engines mounted on buggy vehicles, all-terrain vehicles or the like, or some engines for agricultural implements are provided with a recoil starter, and such engines are started by pulling a recoil rope, which is generally performed by a user.
An example of such known engine provided with a recoil starter is disclosed in Japanese Laid-Open Patent No. 2005-155375.
According to the Japanese Laid-Open Patent No. 2005-155375, the engine provided with a recoil rope obtains electric power from a generator rotated during the start operation of a recoil starter. An ignition operation is performed by the electric power thus obtained from the generator. If an electronic fuel injector is provided, fuel supply is performed by the electric power thus obtained. The engine starting system disclosed in the Japanese Patent Laid-Open No. 2005-155375 exercises ignition control by selecting optimum ignition timing from an ignition map in which ignition timing is set relative to the rotational speed of an engine.
The engine starting system disclosed in the Japanese Patent Laid-Open No. 2005-155375 exercises ignition control by selecting the optimum ignition timing. However, the time when start operation is initiated, i.e., a crankshaft rotational position encountered when the recoil rope is started to be pulled, is not controlled.
In other words, according to the engine starting system of the Japanese Patent Laid-Open No. 2005-155375, the rotation is started from crankshaft rotational positions different each time. Thus, starting performance of the engine has variations, which may result in inefficient and difficult starting of the engine.
The present invention has been made in view of the above-mentioned drawbacks. Accordingly, it is it is one of the objects of the present invention to provide an engine starting system and method that can improve the starting performance of an engine equipped with a recoil starter for easily starting the engine.